This invention relates to refrigerant compressors and in particular to a suction accumulator and the assembly of a suction accumulator and a refrigeration compressor.
Suction accumulators are well known in the refrigeration art and are provided in refrigeration systems to prevent liquid refrigerant from entering the compressor cylinder and thereby causing slugging of the compressor. Such accumulators act as storage reservoirs for liquid refrigerant. The accumulators are constructed to cause the stored liquid refrigerant to flash off into the gaseous state prior to entering the compressor suction tube and the compressor cylinder. This invention relates to a suction accumulator and the assembly of such an accumulator to the housing of a compressor.
Many prior art arrangements have been provided for mounting accumulators in refrigeration systems. However, in the interest of providing a compact refrigeration system and for ease of manufacturing, it is preferable that suction accumulators are mounted directly on the compressor housings. Furthermore, in the interest of achieving a compact refrigeration system it is desired that the space between suction accumulators and the compressor housings be kept very small.
A further desirable feature of a refrigeration system is that very little pressure drop occurs in the suction tube so that suction tube losses will not detract appreciably from the efficiency of the refrigeration system. In order to prevent appreciable pressure drop in the suction tube it is desirable that the length of the suction tube is kept as short as possible and furthermore that the diameter of the suction tube is made as large as possible. In the prior art suction accumulator mounting arrangements these objects have not been achieved. Conventionally a suction accumulator comprises a cylindrical housing having two end walls. The suction tube enters one end wall. Conventionally these end walls have been convex or of frusto-conical shape. One end of the suction tube extends into the accumulator through a central aperture of the end wall. The other end of the suction tube is connected to the casing of the compressor. The suction tube therefore includes a bent portion and the radius of the bent portion is a function of the diameter of the suction tube and the diameter of the accumulator. One such prior art accumulator mounting arrangement is disclosed in copending patent application Ser. No. 670,306 filed Nov. 13, 1984 and assigned to the assignee of record of the present application. In the interest of keeping this prior art assembly compact, the diameter of the suction tube has been made small so that the suction tube can accommodate the rather sharp bend from the accumulator to the compressor housing. This has led to an undesirable pressure drop in the suction tube. It is therefore desired to provide an accumulator mounting arrangement whereby the diameter of the suction tube is maximized.
Another disadvantage of prior art suction accumulator and compressor assemblies has been that the end wall thickness of the accumulator has been relatively thin in order to use a minimum of materials. The problem with this construction is that noise generated by the operation of the compressor has tended to be amplified by this bottom portion of the accumulator which acts as a "drum skin" and resonates at the noise pulse frequency of the compressor. It is therefore desired to provide an accumulator which attenuates rather than amplifies the noise generated by the compressor.